Dentists report on new computerized tomography systems

Discuss uses for diagnosing oral health problems

Cone beam computerized tomography (CBCT) increasingly has become the newest technology for orthodontists to use in diagnosing complicated oral health problems.

Reporting on four new CBCT systems in the December issue of the Journal of Orthodontics are J. Martin Palomo and Mark Hans from the department of orthodontics at the Case Western Reserve University School of Dental Medicine and C.H. Kau and S. Richmond from the department of dental health and biological sciences at the University of Wales’ College of Medicine.

“The long awaited incorporation of the third dimension to our radiographic records is now a reality,” the researchers said, adding “There is still room for improvements; however the CBCT technology appears to be here to stay.”

What started as a prototype for CT imaging in 1967 has evolved into a sixth generation, with better and more focused images and lower radiation exposure for patients. The first generation scanners gave slice-by-slice images. The newest generation of the CBCT scanners sweeps the head and face and provides multiple stacks of images to give a full head view of the bone and tissue structures in three dimensions.

Current available CBCT scanners are: the NewTom 3G from Quantitative Radiology of Verona, Italy; the i-CAT from Imaging Sciences International, from the United States; CB MercuRay from Hitachi Medical Corporation from Japan; and the 3D Accuitomo from J. Morita Mfg Corporation, also from Japan.

What are the benefits of this new technology and their applications to orthodontics? The researchers report:

• The technology generates a wide range of images of the head, teeth and airways in under one minute, reducing radiation exposure to 20 % of convention CT imaging systems.
• The images taken with CBCT technologies are so swift that they can capture a heart beat.
• The technology adheres to radiation-level guidelines provided by the American Dental Association and the British Orthodontic Society to use techniques that reduce exposure to radiation.
• The new 3-D images captures pictures of hard tissues and most soft tissues components, except the color texture of the skin’s surface, enabling orthodontists to detect higher incidences of oral abnormalities such as oral cysts and buried teeth.
• The improved images allow for better airway analyses and management of conditions related to sleep apnea and enlarged adenoids.
• Images from the CBCT technology have additional applications in other specialties of dentistry such as in placing new implants that are increasingly used in place of dentures, remedial efforts for TMJ and for reconstruction of cleft palates and lips.

The researchers report, “The future in orthodontic imaging seems exciting as we discover new frontiers, and as the paradigm in dentistry shifts from landmarks, lines, distances and angles to surfaces, areas and volumes.” They also added that “Orthodontists are beginning to appreciate the advantages that the third dimension gives to clinical diagnosis, treatment planning and patient education.”